Conversations: Optimize your coliform mastitis vaccination protocol

As well-managed dairies lower their bulk tank somatic cell counts, coliform bacteria frequently become the leading cause of clinical mastitis. Coliform bacteria may be responsible for as many as 40% of clinical cases occurring in herds and the majority of peracute cases of clinical mastitis1.

By Tom Van Dyke

Conventional immunization strategies using core antigen bacterins have primarily targeted cows early in lactation (<120 days in milk) according to Ron Erskine, DVM, Ph.D., Michigan State University. He adds, “this period of lactation has often been attributed to be the period of greatest risk for cases of clinical mastitis.”2 While there are many cases of coliform mastitis in early lactation, some dairies may be experiencing more coliform mastitis later in lactation. If coliform mastitis is occurring later, then the conventional dry cow protocols might be insufficient. Ideally, programs should be adapted to the individual needs of each herd based on the history of the disease and the success (or lack of success) of previous vaccination protocols.2

1) Should a dairy farm that is not currently using a coliform mastitis bacterin start doing so?

David Wilson, DVM, Ph.D., Professor from Cornell University’s Quality Milk Services, suggests adoption of coliform mastitis vaccination in herds makes financial sense “when a review of culture of milk of the entire lactating herd indicates 1% or more of the cows to be positive for Escherichia coli, Klebsiella sp, or Enterobacter spp, and/or the rate of clinical coliform mastitis is greater than 4% per month.” 3 Those wanting a more in-depth financial analysis of vaccinating cattle against coliform mastitis should consider working through the partial budget constructed by Degraves and Fetrow.4

If a herd experiences problems with severe coliform mastitis later in lactation, the dairy manager may want to consider adding additional whole herd vaccine doses to the protocol. Low serum levels of antibody titers recognizing gram-negative core antigens have been associated with five-fold increased risk of clinical coliform mastitis.5 Titers to core antigen type vaccines can decline faster than that of other antibodies.6 Maintaining higher antibodies with whole herd vaccinations could be beneficial.

Ask your veterinarian if special attention is warranted due to other gram negative bacteria causing health problems on the dairy.

3) How can the success of coliform mastitis vaccination protocol be enhanced?

Dr. Erskine asserts that “poor management will overcome good vaccines every time.” He emphasizes every effort should be made to minimize exposure to the coliform bacteria by providing “clean, dry bedding, adequate space and cleanliness of cows and balanced nutrition to avoid metabolic disease.”2

Proper storage, handling and timing of administration of the vaccine are also important. Vaccination in times of environmental stress such as excessive heat and humidity should definitely be avoided.

4) What are the differences in the coliform mastitis vaccines with respect to the different protocols?

The commercially available vaccines against coliform mastitis are made from gram-negative bacteria core antigens. They depend on a similar mechanism for immunization and cross-protection, though the mechanism of how the vaccines actually work has not been totally explained.3 The chief differences lie in the original strain of bacteria from which the vaccine is built and the carrier or adjuvant. Differences in label dosage volume, number of doses in conventional protocol, meat withholding and trial results, among others, reflect these formulation differences.

Ask your veterinarian to help evaluate vaccine label recommendations and herd history to choose the best fit for your protocol.